The present invention relates to a method for drying substrates.
European patent application 0 385 536 discloses a method and device for drying substrates after treatment in a liquid. According to the method known from this printed document, substrates are treated for a period of time in a bath that contains a liquid and are then removed so slowly that practically the entire liquid remains within the bath. In so doing, the substrates are brought directly from the liquid into contact with a vapor. The vapor does not condense on the substrate and mixes with the liquid whereby the mixture has a lower surface tension than the liquid. This method, however, is very complicated in practice because vapor is required and must be removed, and, in particular, supply lines and exhaust nozzles for the vapor must be made available.
From U.S. Pat. No. 4,722,752 a device and a method for cleaning and drying of disc-shaped substrates, for example, semiconductor wafers, is known in which the heat energy remaining in the substrates is used to generate a surface tension gradient. External heat is not supplied for improving or accelerating the drying process.
U.S. Pat. No. 4,920,350 shows and discloses a device and a method for cleaning and drying substrates whereby at the surface of the liquid energy in the form ultrasound is supplied to the substrate upon removal. The supplied energy however does not serve for drying but for cleaning.
The washing and drying method known from U.S. Pat. No. 5,368,649 for mechanical or electronic components as well as lenses employs for improvement of the drying method a liquid which is maintained at a pressure that is above atmospheric pressure. The rinsing liquid is heated above the boiling point defined at atmospheric pressure. For the drying process, the workpiece is introduced into a drying chamber in which a sudden decompression takes place so that the rinsing liquid on the workpiece evaporates quickly.
The invention has the object to provide a method in which the substrates during removal from the fluid bath can be dried quickly, at minimal expenditure, without impacting the environment, and without residues forming on the substrates.